Punch, bend and trim device

ABSTRACT

The invention disclosed is a device having means to punch, bend and trim a metal backed printing plate to effect accurate registration onto a press. Registration areas are first provided in proper alignment relative the printing areas of the plate being processed. Next, means are provided for positioning the registration areas in fixed location prior to shearing of the plate along the width and length edges thereof. Shearing of the length, along opposite ends of the plate is accompanied by punching saddle engaging slots, and bending. The plate so processed is ready for accurate introduction into a printing press where the ends are conveniently secured in place about a saddle.

ite States atent 1 ElburnJr.

[ PUNCH, BEND AND TRIM DEVICE [75] Inventor: William H. Eburn, Jr., Westport,

Conn.

[73] Assignee: W. R. Grace 8: Co., New York,

[22] Filed: Feb. 29, 1972 [21] Appl. No.: 230,248

[52] US. Cl. ..72/324, 72/319, 72/326, 72/333, 72/335 [51] Int. Cl. ..B2ld 43/28 [56] References Cited UNITED STATES PATENTS 3,657,952 4/1972 Brockbank et a1. ..83/102 3,635,112 1/1972 Johnson 3,605,535 9/1971 Love et al ..83/40 [451 May 29, 1973 Primary Examiner-Richard J. Herbst Assistant Examiner-James R. Duzan Attorney-Eugene M. Bond [57] ABSTRACT The invention disclosed is a device having means to punch, bend and trim a metal backed printing plate to effect accurate registration onto a press. Registration areas are first provided in proper alignment relative the printing areas of the plate being processed. Next, means are provided for positioning the registration areas in fixed location prior to shearing of the plate along the width and length edges thereof. Shearing of the length, along opposite ends of the plate is accompanied by punching saddle engaging slots, and bending. The plate so processed is ready for accurate introduction into a printing press where the ends are conveniently secured in place about a saddle.

2 Claims, 13 Drawing Figures I PUNCH, BEND AND TRIM DEVICE This invention relates to a device having means to punch, bend and trim a metal backed printing plate in a precise and accurate manner. More particularly, the present device provides means for processing a printing plate prior to introduction onto a press saddle by accurately shearing the edges thereof while punching saddle engaging slots along opposite ends of the plate.

It is known that printing plates may be prepared using photocurable compositions. One example of such a method is that described in US. Pat. No. 3,615,450. In preparing such plates especially when using a thin metal support plate such as of aluminum, steel or the like, it becomes necessary to align the backing relative to the printing areas upon introduction onto a saddle of a printing press. The present invention provides an apparatus which processes flexible thin printing plates, especially those with a thin metal support backing such as of aluminum or steel, for direct introduction accurately onto a saddle of a printing press.

When a printing plate is prepared by exposing a photocurab le composition through a transparency, registration areas are provided in non-printing areas of the transparency such that upon exposure the registration areas become part of the photocured areas of the printing plate. These registration areas align with the printing area and, as will be subsequently apparent, the registration areas eliminate great concern for alignment of the metal backing at the time of exposure.

Having so prepared a printing plate, the finally developed plate is ready for processing in the apparatus of the present invention.

Generally stated, the present invention includes means for positioning a printing plate having registration areas disposed on a thin metal backed printing plate accurately aligned relative to the printing areas thereon, means for fixing the positioned plate from movement during subsequent processing, trim or shearing elements disposed for shearing the plate along a width measurement thereof, trim or shearing elements in association with slot punching means both disposed for shearing and punching the plate along opposite ends of a length measurement thereof, and bending means in association with the end shearing and punching means for bending the plate along lines near opposite ends thereof. In an embodiment device, means are provided for stretching in the length direction, the bended ends to insure against spring return of the edges to original position.

Practice of the present invention will become more apparent from the following detailed descriptions taken -in connection with the accompanying drawings wherein like numerals refer to similar elements throughout the several views.

FIG. 1 is a perspective view of thedevice of the present invention;

FIG. 2 diagrammatically illustrates as a perspective view exposing through a transparancy to efiect positioning of registration areas on a printing plate;

FIG. 3 shows a side elevational view in partial section illustrating the positioning of registration areas in fixed location;

FIG. 4 similarly taken to FIG. 3, illustrates clamping prior to shearing along the length of the plate;

FIG. 5, similarly taken to FIG. 4-, illustrates shearing or trimming of opposite ends along the length of the plate;

FIG. 6 is a side elevational view in partial section taken degrees removed to that of FIG. 5, and illustrates clamping prior to shearing of edges and punching of saddle engaging slots along opposite ends of the plate;

FIG. 7 similarly taken to FIG. 6 except along one edge, illustrates shearing of edges and punching of saddle engaging slots;

FIG. 8 similarly taken to FIG. 7 illustrates bending of the opposite ends of the plate, which may be followed, if desired, by stretching in the direction of the arrow;

FIG. 9 is a perspective top view of the finally processed plate ready for mounting onto a saddle;

FIG. 10 presents a partial side elevational view of one of the shearing elements which trims edges along the width measurement including means for removing the elements from shearing position;

FIG. 11 presents a rear elevational view of the shearing element of FIG. 10;

FIG. 12 presents aperspective view of the end trimming and slot punching element of the present device; and

FIG. 13 presents a partial side elevational view of the elements associated with the end trimming and slot punching means of FIG. 12.

Referring to the drawings, FIG. 1 illustrates device 2 having vacuum table 8, knee actuated vacuum control 6, pivotal register arms 28, width shear elements 36 disposed for trimming opposite edges of a printing plate and end punch, bend and trim elements lll, also disposed for processing opposite edges of a printing plate 90 degrees removed from those of elements 36. Control l3 initiates operation of the device as desired.

Referring to diagrammatical FIGS. 2-9, the present invention initially involves providing registration areas aligned relative to the printing plate area. In FIG. 2, printing plate 10 is illustrated having a metal backing 12, a photocurable polymer 14 with printing area 16, and registration areas 18 formed thereon. The printing area and registration areas result by exposing transparency film 20 having printing areas 22 and registration areas 24 thereon, using a light source 26 for exposure such as ultra-violet light.

After exposure of the plate has been effected, with subsequent processing as may be necessary for development, printing plate 10 is then processed at the step of FIG. 3. The printing plate 10 having metal backing 12 is placed on vacuum table 30 or other convenient support whereon it is aligned using aligning means illustrated as pivotal register arms 28 which cooperate with registration areas 18. The printing plate is held in fixed position by a suitable means such as by vacuum ports 32 receiving vacuum from a convenient source by line 34. It is recognized that other means may be used to secure the plate in fixed position provided that such means does not interfere with subsequent processing steps hereof and also that damage of the printing surface does not result.

After the printing plate has been registered and fixed in position such as that illustrated in FIG. 3, the plate is sheared of pieces 37 along the width thereof as illustrated in FIGS. 4-5. Thus, because of the registration areas and by fixing the plate in position, accurate shearing of the width edges relative the printing area is accomplished. Shearing of the width edges may be accomplished by shearing means 36 either prior to or subsequent to shearing of the ends of the plate, as desired.

The ends of the plate are sheared, punched, and bended, in sequence as desired, such as illustrated in FIGS. 68. With plate 10 in fixed position by elements 39, shearing means 38 engages the plate for accurately shearing the end edges of the plate relative to the printing areas. Punching of saddle engaging slots may be accomplished by punch 40 illustrated as a component of shearing means 38, and securing or clamping elements 39.

In order to avoid movement of plate 10 from fixed position, the sequence of end shearing, punching and bending is accomplished without release of the plate by elements 39 either during or between each processing step. Thus, once the ends of the plate are engaged for end processing by elements 39, the sequence of shearing, punching and bending with optional bend stretching is accomplished before the plate is released. Excess material 41 trimmed from the edge of the plate is discarded.

In FIGS. 68, ends of metal backing 12 of printing plate 10 in fixed position over vacuum table 30, are engaged by elements 39, shearing means 38 and punch 40. Elements 39, shearing means 38 and punch 40 are disposed such that they may rotate as indicated by arrow 43 to effect bending from FIG. 7 to FIG. 8, and further being disposed such that they may stretch the plate during bending in the direction of arrow 45. Stretching is optionally desired in instances when metal backings are characterized such that bends have a spring tendency to return to normal flat position, i.e., spring type steel or the like. In such instances, stretching during bending has a tendency to insure retention of the bend. After bending has been accomplished, the end processing means release the plate which is now ready for introduction onto a saddle.

After the sequence of FIGS. 68, the means used to retain the plate in fixed position, such as vacuum table 30, is released thus providing a printing plate such as that illustrated in FIG. 9.

FIG. 9 illustrates finally processed printing plate 44 having accurately positioned edges 46 bended for mounting by way of slots 48 onto the saddle of a printing press.

FIGS. 10-11 illustrate means for shearing the plate along the width edges thereof. The shearing means 50 includes shearing blade 52 which may be operated by solenoid 54. Upper blade 56 is removably disposed by spring biased bolt 58 secured onto frame 60, which frame pivots about axle 62 in the direction of arrow 64. Pivotal movement is effected by piston 66 which moves pivotal plate 68 positioned about rod 70 in the direction of arrow 72. Arm 71 connects plate 68 to frame 60. In non-operational position, shearing means 50 is pivoted downwardly. Upon signal, piston 66 is actuated causing the piston rod 67 to extend by pivoting plate 68 about axle 69 thus raising shearing means 50 to the position illustrated in FIG. 10. Either automatically or manually, solenoid 54 is actuated causing blade 52 in cooperation with blade 56 to trim the edge of a thin metal support sheet of a printing plate disposed therebetween. Shearing means 50 is joined to housing 51 as desired.

FIG. 12 illustrates punch and trim bar 76 formed of several elements 78 for punching saddle engaging slots near each end thereof, and end trimming edge 80. The end trimming edge may include trimming block 82 as desired. The elements 78 and trimming block 82 may be replaced after wear by removing plate 84 or attachment means 86 such as bolts or the like. Removable bar 88 provides a plate contact surface which cooperates with a second plate during clamping, shearing and punching of the printing plate edges. The combination of punching elements 78, and trimming block 82 slide in the direction of arrow 89 by movement of platform 90, using suitable means such as pistons, solenoids or the like.

FIG. 13 illustrates cooperation of elements to effect bending, trimming and punching of the plate ends.

Piston 92 upon being actuated in the direction of arrow 93 causes lever 94 to rotate about rod 96. This movement causes arm 98 to pivot head 100 into operating position in the direction of arrow 101, from nonoperating down position. Simultaneously, by bar 102, oppositely disposed head 104 pivots in the direction of arrow 105 to operating position by movement of levers 106 and 107 about axle 108.

Operation of the remaining elements associated with head 104 is the same as that for head 100, although for convenience of illustration, they are not all shown.

Plate 110 has ends within the pivot head 100 for processing by punch and trim bar 76 operating by solenoid l 12.

The punching and trimming step is accomplished by movement of solenoid 1 12. The bending step is accomplished by actuating solenoid 114 in the direction of arrow 116 with pivotal movement being effected about axle 118 illustrated generally.

After the bending, stretching is accomplished by further actuating piston 92 in a direction opposite to that of arrow 93 while head 100 is in the pivoted or bending position taken in the direction of arrow 116.

Thus, operation of the present devices proceeds as follows, either automatically or semi-automatically as desired.

An operator places a sheet to be worked onto the vacuum plate of the device and a signal is given to the register arms to come down into position.

The operator at this time locates the sheet so that the register arms orient themselves into the registration spots provided on the sheet. Once the sheet is located under the register arms, a vacuum punp in the device is turned on by the operator and the sheet is then held down to the plate by vacuum pressure.

The operator will then depress cycle start push buttons. At this point the cycling of the device may be fully automatic. The device will shear the sheet to width, shear and punch the ends to size, and put in a bend at the ends of the sheet. It will then turn off the vacuum and release the sheet.

The device cycle starts by placing a properly registered and imaged plate onto the vacuum platen. The registration arms with locator pins are lowered onto the plate by depressing cycle start buttons. The plate is adjusted on the platen until the registration spots on the plate are fitted to the locator pins. The vacuum starts by pressing a knee switch located in the center front panel of the device. The vacuum holds the plate in place during subsequent operations.

After registration is effected, the registration arms rise out of the work area of the machine and reset. The registration arms must be in an upright position, out of the way of the shear blades, before the device will start its automatic cutting, trimming, and punch-bending cycle.

The side shears erect, and trim the plate, after which the side shears retract and return to the rest position. Next, the punch shear heads erect, proceed upward and end cut the sheet to size and pierce the slots for the saddle lock. The punch-shear heads while remaining closed apply about a 70 degree bend to the punched ends of the plate by rotating the closed heads from the vertical to the near horizontal position.

The plate is stretched by the punch-shear heads while they are in a closed and bent position. Stretching continues until the plate is drawn uniformly smooth over the vacuum platen.

Air pressure is applied to the rod end of the punch tilt cylinder. At this time the punch tilt cylinders will attempt to return to their open position. However, since the sheet has been clamped in the punch, the attempt at returning to the open position will put a tension onto the sheet and set the bend. The punch-shear heads relax to the upright position which relieves the stretch on the sheet. The punch shear dies retract from the punched and bent metal sheet, return from the near horizontal to the normal upright vertical position and return to the rest or out position.

All copy for printing must be registered accurately on the camera copy board in relation to registration marks which will be carriedthrough the platemaking operation. These registration marks must be designed so as to produce a polymer hole or slot on the imaged plate. The polymer hole or slot registration marks provide accurate image registration when mated to the registration arms of the present punch, bend and trim device. This system provides sheet trimming, punching and bending which yields accurate metal and image placement on press.

Although the present device has been described for convenience with regard to photocuring techniques, it will be apparent that it is readily applicable to other printing plate processing techniques such as photoengraving, thermal engraving, and direct etching.

The printing plates formed by the process of the instant invention may be employed in various types of printing including but not limited to intaglio printing, flexographic printing, letterpress printing, dry offset printing, and the like.

The various elements of the present apparatus unless otherwise indicated, may be secured to adjoining elements by any suitable means such as bolts, welding, rivets or the like. In addition, auxiliary support or reinforcement members may also be included as part of the apparatus where required. It is also apparent that solenoid members or piston members may be interchanged as desired or replaced by equivalent mechanical means.

Although a preferred embodiment of the invention has been illustrated herein, it is to be understood that various changes and modifications may be made in the construction and arrangement of elements without departing from the spirit and scope of the invention as defined.

What is claimed is:

l. A device for processing a printing plate, said device comprising in combination, means for positioning a printing plate having registration areas disposed on a thin metal backed printing plate accurately aligned relative to the printing areas thereon, means for fixing the positioned plate from movement during subsequent processing, trim or shearing elements disposed for shearing the plate along a width measurement thereof, trim or shearing elements in association with slot punching means both disposed for shearing and punch ing the plate along opposite ends of a length measurement thereof, and bending means in association with the end shearing and punching means for bending the plate along lines near opposite ends thereof.

2. The device of claim 1 wherein means are provided for stretching in the length direction the bended ends to insure against spring return of the edges to original position. 

1. A device for processing a printing plate, said device comprising in combination, means for positioning a printing plate having registration areas disposed on a thin metal backed printing plate accurately aligned relative to the printing areas thereon, means for fixing the positioned plate from movement during subsequent processing, trim or shearing elements disposed for shearing the plate along a width measurement thereof, trim or shearing elements in association with slot punching means both disposed for shearing and punching the plate along opposite ends of a length measurement thereof, and bending means in association with the end shearing and punching means for bending the plate along lines near opposite ends thereof.
 2. The device of claim 1 wherein means are provided for stretching in the length direction the bended ends to insure against spring return of the edges to original position. 